Airship



Jan' 10, 1933. M. SCHIRMER 1,894,245

' AIRSHIP Filed Dec. 22, 1930 Patented Jan. 10, 1933 UNITED STATESPATENT OFFICE MAX SCHIRMER, OF

.FRIEDRICHSHAFEN, BODENSEE, GERMANY, ASSIGNOR TO LUFT- SCHIFFBAUZEPPELIN GESELLSCHAFT MIT BESCHRANKTER HAFTUNG, OF FBIED- l RICHSHAFEN,BODENSEE, GERMANY AIRSHIP Application led. December 22, 1930, Serial No.509,985, and in Germany December 23, 1929.

My invention relates to airships and has special reference to thestabilizing fins of such ships which generally are alfixed thereto intheir rear part for the purpose of stabilizing the ship in flight.

The main object of my invention is to increase the eciency of such a finin a most simple way and without increasing the surface or area thereof.

According to my invention I interrupt the surface of the fin by a slitand I prefer to arrange this slit so as to be substantially parallel tothe root edge of the iin, that is the edge where the iin meets theairship body.

This interruption in the surface of the stabilizing iin has the eifectof materially increasing its stabilizing efiiciency as compared withthat of airship fins which are not provided with such a slit because thepressure on the iin at its edges is reduced, especially with fins oflarge area. Of course, in certain cases it may be advisable to have notonly one slit but several of such slits arranged in one iin.

Furthermore, according to my invention, this slit which runs more orless parallel to the airships longitudinal direction at its rear endportion is broadened, so the slit is of substantially greater width atits rear end than over the main portion of its length.

This new feature is of special importance with airships having fins withrudder or elevator surfaces arranged in continuation of the linsurfaces, as this is usual now-adays. A further increase in eihciency isattained thereby.

It has become usual to make the construetion of such fins so that theyare more or less self-supporting, which means that they have a certainthickness at their root where they are fixed to the airship body andtaper towards their outer edge. In surfaces of this kind theinterrupting slits, according to the invention, are also provided withmore or less tapered edges.

The relative tests of my new fin construction in the wind tunnel ascompared with the old known kind have proved a considerable increase ofstabilizing eiiiciency.

Having .given a general description of my invention I now want to pointit out more in detail having reference to the drawing which representsan example embodying my invention.

Fig. l is a view on the rear portion or stern ofV an airship. It may betaken as an elevation or as a plan View; in the following part of thespecification it is considered to be a side view.

Fig. 2 is a vertical section through lower fin, taken on line 2-2 ofFig. 1; whereas Fig. 3 is a horizontal section through the rear portionof the lower iin, taken on line 3-3 of Fig. l.

The rear portion of the airship is designated by the numeral l. There isa lower vertical fin 4 and an upper vertical iin 5. A horizontal fin isindicated at 6. rThe edge where the lins meet the airship body is shownat l.

There is a slit 8 in each of the fins running substantially parallel toedge 7 at a comparatively small distance therefrom. This slit at itsrear end has a portion 9 which is considerably wider than the mainportion of the slit which has substantially parallel edges. In theexample represented this wider portion extends to the very root of thefin. There are rudders l() arranged in the continuation of tins 4, 5, 6.

As may be seen from Fig. 2 the fins are assumed to be of so-calledbodily self-supporting construction, having a certain thickness at theirroot edges 7 and tapering towards their outer edges. In the same figurethe edges of slit 8 are shown rounded or tapered; and also the rear edgeof the wider portion 9 is tapered, as can be taken from Fig. 3.

This wider rear portion 9 of slit 8 allows for a greater amount of airto iiow from one side of the iin to its other side just in front of thefollowing rudder (or elevator).

I do not want to be limited to the details described or shown in thedrawing as many variations will occur to those skilled in the art.

What I claim is:

l. An airship iin being provided with a substantially longitudinallyextending slit,

the

the main portion of said slit having substantially parallel edges, therear portion being of considerably greater width than the main portion.

2. An airship lin of self-supporting body construction and having asubstantially longitudinally extending slit, said slit having taperededges.

' 3. The stern of an airship comprising; the mrportion of the airshipbody; a stabilizing n fixed to said body; a plane adapted to bepositioned at different angles relative to said lin and fastened to therear edge thereof; said fin being provided with a slit of comparativelysmall Width running substantially parallel to the edge in which saidairshjp body and said lin meet and in relatively Small distance fromsaid edge; said slit at its rear end being of considerably broader Widththan over its main length.

MAX SCHIRMER.

